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5.3 Detail of Modbus Register
TEMPERATURE
Parameter range
-4000-8000 corresponds to -40.00~80.00
Default: none
Parameter storage
none
Meaning: the measured value of the temperature, negative for complement representation.
For example: if the return value is 0702H (of 16 hexadecimal, source code), the first byte is 07, the
second byte and the low byte is 02h, then the temperature for the measured value (07H*256 02h)
/100=17.94.
If the return value is FF05H (16 - band, the complement), the first byte is FFH, low second byte is 05H,
then temperature measurement value ((FFH*256 05H) -FFFFH-1H) / 100 = FF05H-FFFFH-1H Celsius
/100=-2.5.
VWC --- volumetric water content
Parameter range
0-10000 corresponds to 0-100%
Default: none
Parameter storage
None
Significance: volumetric water content measurements.
For example: if the return value is 071DH (16 Decimal), the first byte of the high byte is 07H, second
bytes of low byte is 1DH, then the measured value is (1DH 07H*256) /10000= (7*256 29) =1821.
representative volume water content is 18.21%.
EC --- electrical conductivity
Parameter range
0-20000 corresponds to 0-20000us/cm
Default: none
Parameter storage
None
Significance: electrical conductivity measurement.
For example: if the return value is 071DH (in hexadecimal), the first byte is 07, the second byte and the
low byte is 1dh, then conductivity measurement value (07H*256 1dh) / 10000 = (7*256 29) on behalf of
the =1821. soil conductivity 1821us/cm